Display screen or portion thereof with transitional graphical user interface



FIG. 1 is a front view of a display screen or portion thereof withtransitional graphical user interface showing a first image of theclaimed design;

FIG. 2 is a front view showing a second image thereof; and,

FIG. 3 is a front view showing a third image thereof.

The transitional graphical user interface transitions between thefigures. The appearance of the transition is sequential from FIG. 1 toFIG. 3. The process or period in which an image transitions to anotherimage forms no part of the claimed design.

The longer-length broken-line showing of a display screen and theintermediate-length broken-line showing of a display screen boundary,are included for the purpose of illustrating environmental structure andform no part of the claimed design. The remaining broken lines showelements of the graphical user interface that form no part of theclaimed design.

CLAIM The ornamental design for a display screen or portion thereof withtransitional graphical user interface, as shown and described.